52 research outputs found

    Wing colour properties do not reflect male condition in the American rubyspot (Hetaerina americana)

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    Adult males of the American rubyspot (Hetaerina americana) dispute riverine territories where females arrive to mate. On the wing basis, these males bear a red pigmentation spot whose area correlates with territorial disputes and mating rate: males with larger spots are more successful. This is explained by the fact that spot size correlates with fat muscular reserves which fuel flight during territorial intrusions. To further our understanding of sexual selection acting on the spot, here we have examined possible differences in three spot colour properties (red chroma, hue and brightness) in three distinct adult male ages [young, middle-aged (when males are more likely to defend a territory) and old], social status (territorial and non-territorial in middle-aged males), and under two potentially, energetically and costly situations: when faced with an immune challenge [comparing a nylon-implanted male group vs. a non-implanted male group in two ages, teneral (previous to colour formation) and middle-aged] and low diet levels (comparing a male set of middle-aged animals that received food ad libitum vs. a male set that received no food). Our results indicate no change in colour properties across any of these comparisons. Taken together, these and previous results suggest that only spot size but not the spot characteristics we measured here, is sexually selected in males of this species at least in terms of pre-copulatory male-male competition. That some of these colour properties have been related to male condition in other calopterygid damselflies cannot be generalized to the American rubyspot.1131094495

    Association between the Xba I polymorphism of APOB gene and plasma lipid level in Mexican patients with coronary artery disease

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    Some studies, that consider polymorphisms of the apolipoprotein B (APOB) gene as risk factors for coronary artery disease (CAD), have reported discordant results. The aim of the present study was to search for associations between plasma lipid profiles with the DNA Xba I polymorphism of the APOB gene in CAD patients diagnosed by angiography (CAD+). In the present study we compared 114 Mexican patients (80 men and 34 women) with CAD+ and 132 control patients (59 men and 73 women) without evidence of ischemia or arterial damage (CAD The frequency of X+/X+ genotype of Xba I polymorphism, in CAD+ group, was 23% (26/114) compared with 8% (11/132) in the CAD- (OR 3.25, p = 0.002). The patients with X+/X+ for the Xba I genotype APOB gene had higher concentration of triglycerides (TG) and VLDL in plasma than CAD- (p < 0.05). The genotype X+/X+ in the CAD had an effect increasing the TG and VLDL plasma levels when compared with individuals with X-/Xand X-/X+ genotypes. The present study indicated that the X+X+ genotype of Xba I polymorphism is associated with CAD+ patients and high plasma levels of TG and VLDL, in the Mexican population

    Association between the Xba I polymorphism of APOB gene and plasma lipid level in Mexican patients with coronary artery disease

    No full text
    Some studies, that consider polymorphisms of the apolipoprotein B (APOB) gene as risk factors for coronary artery disease (CAD), have reported discordant results. The aim of the present study was to search for associations between plasma lipid profiles with the DNA Xba I polymorphism of the APOB gene in CAD patients diagnosed by angiography (CAD+). In the present study we compared 114 Mexican patients (80 men and 34 women) with CAD+ and 132 control patients (59 men and 73 women) without evidence of ischemia or arterial damage (CAD The frequency of X+/X+ genotype of Xba I polymorphism, in CAD+ group, was 23% (26/114) compared with 8% (11/132) in the CAD- (OR 3.25, p = 0.002). The patients with X+/X+ for the Xba I genotype APOB gene had higher concentration of triglycerides (TG) and VLDL in plasma than CAD- (p < 0.05). The genotype X+/X+ in the CAD had an effect increasing the TG and VLDL plasma levels when compared with individuals with X-/Xand X-/X+ genotypes. The present study indicated that the X+X+ genotype of Xba I polymorphism is associated with CAD+ patients and high plasma levels of TG and VLDL, in the Mexican population

    Methylenetetrahydrofolate reductase C677T polymorphism and Factor V Leiden variant in Mexican women with preeclampsia/eclampsia

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    The etiology of preeclampsia is still a matter of controversy. An association between hyperhomocysteinemia and preeclamptic patients has been described. A common missense mutation in the methylenetetrahydrofolate reductase (MTHFR) gene is associated with increased plasma homocysteine concentrations. In addition, the polymorphism of gene encoding for Factor V Leiden G1691A is associated with a prothrombotic state in heterozygous subjects. Both mutations in these thrombophilic proteins appear to have different prevalence in the general population and in patients with preeclampsia/eclampsia (PE/E). We studied single nucleotide polymorphisms for MTHFR C677T and coagulation Factor V Leiden in 33 Mexican patients with PE/E as a genetic risk factor for these diseases, comparing with a normotensive pregnant control group. The genotype and allele frequencies of MTHFR C677T and Factor V Leiden mutations between Mexican women with PE/E and healthy controls were not different. We conclude that these polymorphisms do not contribute in the etiology of PE/E as it has been reported in other populations. � 2005 Elsevier Inc. All rights reserved
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